The equilibrium constant
In a certain experiment a student starts with 0.862 atm of N2 and 0.373 atm of H2 in a constant-volume vessel at
Interpretation:
The partial pressure of the species present in the given equilibrium reaction is to be calculated with given
Concept introduction:
Equilibrium constant for gas phase reactions is written in terms of the partial pressures of the species present in the reactionas the concentration of gases is directly proportional to the partial pressures. The equilibrium constant in terms of partial pressure is denoted by
Equilibrium constant is the ratio of the concentration of reactants and products present in the chemical reaction.
For a general reaction:
The general formula for writing equilibrium expression for the reaction is given as:
Here,
A and B are reactants, C is products, and
For the general reaction:
The general formula for writing equilibrium expression for the reaction is given as:
Here,
A and B are reactants, C and D are products, and
Equilibrium constants of gas phase reaction are written in terms of partial pressures because concentration of gases is directly proportional to partial pressures.
The relationship between
Answer to Problem 104AP
Solution:
Explanation of Solution
Given information:
The given balanced equation is as follows:
The initial change equilibrium table for the reaction is as follows:
The equilibrium constant expression for the reaction is given as follows:
Here,
Substitute the values of
As the value of
The partial pressure of
The partial pressure of
The partial pressure of
The partial pressures of
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Chapter 15 Solutions
Chemistry
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- Nitrosyl chloride, NOC1, decomposes to NO and Cl2 at high temperatures. 2 NOCl(g) ⇌ 2 NO(g) + Cl2(g) Suppose you place 2.00 mol NOC1 in a 1.00–L flask, seal it, and raise the temperature to 462 °C. When equilibrium has been established, 0.66 mol NO is present. Calculate the equilibrium constant Kc for the decomposition reaction from these data.arrow_forwardGaseous acetic acid molecules have a certain tendency to form dimers. (A dimer is a molecule formed by the association of two identical, simpler molecules.) The equilibrium constant Kc at 25C for this reaction is 3.2 104. a If the initial concentration of CH3COOH monomer (the simpler molecule) is 4.0 104 M, what are the concentrations of monomer and dimer when the system comes to equilibrium? (The simpler quadratic equation is obtained by assuming that all of the acid molecules have dimerized and then some of it dissociates to monomer.) b Why do acetic acid molecules dimerize? What type of structure would you draw for the dimer? c As the temperature increases would you expect the percentage of dimer to increase or decrease? Why?arrow_forwardCyclohexane, C6H12, a hydrocarbon, can isomerize or change into methylcyclopentane, a compound of the same formula (C5H9CH3) but with a different molecular structure. sssss The equilibrium constant has been estimated to be 0.12 at 25 C. If you had originally placed 0.045 mol of cyclohexane in a 2.8-L flask, what would be the concentrations of cyclohexane and methylcyclopentane when equilibrium is established?arrow_forward
- Write equilibrium-constant expressions Kp for each of the following reactions: a N2O4(g)2NO2(g) b 2NOBr(g)2NO(g)+Br2(g) c 2SO3(g)2SO2(g)+O2(g) d 4NH3(g)+5O2(g)4NO(g)+6H2O(g)arrow_forwardIn a 3.0-L vessel, the following equilibrium partial pressures are measured: N2, 190 torr; H2, 317 torr; NH3, 1.00103 torr. N2(g)+3H2(g)2NH3(g) (a) How will the partial pressures of H2, N2, and NH3 change if H2 is removed from the system? Will they increase, decrease, or remain the same? (b) Hydrogen is removed from the vessel until the partial pressure of nitrogen, at equilibrium, is 250 torr. Calculate the partial pressures of the other substances under the new conditions.arrow_forwardFor the equilibrium 2 SO2(g) + O2(g) 2 SO3(g) Kc = 245 (at 1000 K) the equilibrium concentrations are [SO2] = 0.102, [O2] = 0.0132, and [SO3] = 0.184. The concentration of SO2 is suddenly doubled. Show that the forward reaction takes place to reach a new equilibrium.arrow_forward
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